1. Field of the Invention
The present invention relates generally to industrial conveyor mechanisms, and more specifically to a conveyor apparatus for accepting individual units, or "slugs," of a product and stacking the slugs for packaging in a packaging machine. The present slug loader accepts horizontally disposed individual slugs and stacks them back to face using both fixed and automatically extending and retracting fingers or pins for holding the slug assemblies on a conveyor line. The stacked assemblies are then merged from two (or more) stacking sections, into a single line for packaging.
2. Description of the Related Art
The automated processing of various articles is a goal of practically every industry, in order to save the costs of labor. Even when a particular operation has been automated to a certain extent, there may be some means for increasing the efficiency of the existing automation, e. g., by providing a machine which is capable of performing the work of two or more previously existing machines, or perhaps providing a more efficient means of accomplishing a task handled by an earlier machine.
This is particularly true in the food processing industry, where automation is particularly valuable in reducing or eliminating food handling by human personnel and accompanying sanitation concerns, and where food articles must be handled extremely rapidly for economical operation due to the relatively inexpensive cost of each unit. Accordingly, various automated devices have been developed in the past for automatically baking, assembling, and/or otherwise processing various food articles (cookies, crackers, etc.), and then stacking them for packaging.
One such machine, made by the Peters Company, is used for forming and transferring "slugs," or stacks of a food article, for packaging. However, the Peters slug loading machine has its drawbacks. First, the Peters machine (as well as others) utilizes overhead mechanisms to advance the slugs, which may result in lubricants and/or other foreign matter falling and contaminating the food. Also, the Peters machine transfers the formed slugs ninety degrees from their orientation when being formed, and then requires another ninety degree turn to the wrapping machine. This leads to higher breakage rates and operating costs with the Peters machine, compared to the present infeed slug loader with its increased operational efficiency.
Accordingly, a need will be seen for an automated infeed slug loader which turns individual units of a generally flat product from a horizontal tandem orientation to a stacked configuration for packaging. The present machine accomplishes this function by routing the products up a slope and gathering them on the slope, where gravity retains the stack against the stacking wheel until a lower or following pin or finger on the conveyor line reaches the stack. After a predetermined number of the units are gathered to form the slug, an upper or forward pin or finger captures the uppermost or forwardmost unit, sandwiching the elements of the slug between the rearward and forward pins.
Preferably, two or more such assemblies are provided, which merge the slugs formed on each line into a single line for more rapid packaging of the product. More than two such lines may be formed, merging into a single packaging line, if so desired.
A discussion of the related art of which the present inventor is aware, and its differences and distinctions from the present invention, is provided below.
U.S. Pat. No. 3,743,118 issued on Jul. 3, 1973 to Rene Fluck, titled "Stacking Device For Regularly Shaped, Flat Articles, For Examples Biscuits Or Cookies," describes a conveyor system in which longitudinally and laterally disposed cookies or the like are gathered in individual lateral rows of a conveyor. A mechanism stacks the cookies laterally across the conveyor, to form a single stack of cookies in each lateral row. Each stack is then turned ninety degrees to drop into a discharge slide. In contrast, the present mechanism gathers cookies or the like from two or more tandem rows and stacks them from below to form slugs, with each slug being transferred longitudinally along a conveyor line. The present system also merges two or more lines into a single line, which mechanism is not disclosed in the U.S. Patent to Fluck.
U.S. Pat. No. 3,927,508 issued on Dec. 23, 1975 to William A. Campbell, III, titled "Article Loading Machine," describes a conveyor system in which plural, previously stacked slugs or groups of cookies or the like make a ninety degree turn down plural chutes, to be carried as vertical stacks to another ninety degree turn where they are dropped into trays for packaging. The Campbell, III '508 U.S. patent does not disclose any mechanism for stacking the cookies or forming slugs of cookies or other articles, as provided by the present conveyor mechanism. Moreover, the Campbell, III '508 U.S. patent does not disclose any shallow angular merging of two or more slug lines into a single coplanar slug line, as provided by the present conveyor system invention.
U.S. Pat. No. 4,590,743 issued on May 27, 1986 to Timothy W. Hardage, titled "Tray Loading Method And Apparatus," describes a system having a plurality of conveyor belts in series, each operating at different speeds at different times so as to group cookies or other articles thereon at some points, and spread them apart at other points. A turning wheel is used to turn cookies from a horizontal position to stacked slugs, but the slugs are horizontally disposed within a drum which turns to deliver the cookies to trays below the drum. The present infeed slug loader system uses the turning wheel to stack the cookies or other articles on a sloped conveyor run, with gravity holding the articles in the stack while it is being formed. The stack is then transferred up the slope to a horizontal run, where it is merged with one or more additional runs for transfer to a packaging machine.
U.S. Pat. No. 4,712,356 issued on Dec. 15, 1987 to Timothy W. Hardage et al., titled "Tray Loader," describes a machine which is closely related to the machine described in the '743 U.S. patent to the same inventor, discussed immediately above. The primary difference is that the mechanism of the '356 U.S. patent includes moving fingers or pins within the stacking drum, to hold the cookies in the desired vertical alignment. The present invention accomplishes the holding of the stacks during formation, by means of gravity and the sloped ramp along which the stacks or slugs are formed, rather than using a relatively complex mechanism for adjusting the positions of the fingers or pins during stacking, as in the Hardage et al. '356 U.S. patent. Also, the '743 U.S. patent does not disclose any means for merging two or more stacking lines into a single packaging line, as provided by the present infeed slug loader machine.
U.S. Pat. No. 4,736,570 issued on Apr. 12, 1988 to Timothy W. Hardage et al., titled "Automatic Cookie Loading Machine With Double Discharge," describes a conveyor system in which cookies are directed to one or the other of two sides thereof, and transferred down a sloped belt. The cookies are held in place on the belt by closely placed overlying conveyors. The cookies are essentially on edge at this point, and drop into an intermediate receptacle. When the receptacle is filled, it is inverted to drop the cookies into a tray positioned below the receptacle. No stacking of slugs using an upward slope, or merging of plural lines into a single line, is provided by the Hardage et al. '570 U.S. patent.
U.S. Pat. No. 5,014,496 issued on May 14, 1991 to Bill E. Davis et al., titled "Method Of And Apparatus For Continuous Bakery Product Wrapping," describes a wrapping machine, as opposed to a stacker or loading machine as provided by the present infeed slug loader. No disclosure is made in the Davis et al. '496 U.S. patent of any means of stacking baked or other goods to form slugs, nor for merging two or more lines of slugs into a single line for efficient wrapping or packaging thereof, as provided by the present infeed slug loader invention.
U.S. Pat. No. 5,052,166 issued on Oct. 1, 1991 to Beda Ziegler et al., titled "Method And Apparatus For Continuous Package Making," describes a wrapping machine using a partial vacuum for assisting in holding the wrapping about the product. No means of forming stacks or slugs of a product is disclosed by Ziegler et al., as the disclosed apparatus shows the slugs as already having been formed in a previous operation before arriving at the Ziegler et al. wrapping machine. Moreover, the Ziegler et al. apparatus does not provide two or more lines which are merged into a single line, as in the present apparatus. Also, while the Ziegler et al. apparatus discloses leading and trailing fingers for holding the leading and trailing articles in a stack or slug, no means is disclosed for folding or articulating any of the fingers relative to the conveyor line to which they are secured, which means is provided for the leading fingers or pins of the present infeed slug loader invention.
U.S. Pat. No. 5,095,684 issued on Mar. 17, 1992 to William D. Walker et al., titled "On Edge Cookie Loader," describes an apparatus in which stacking of cookies is accomplished by progressively slower conveyor belt runs, causing the cookies to stack or pile up behind one another. The stacking run is a strictly horizontal process, with no slope being provided for assisting in the stacking, as with the present slug loader device. Moreover, the mechanism comprises only a single line, rather than the two or more lines which are merged into a single line, as in the present slug loader machine. The Walker et al. mechanism requires additional electronic componentry for counting the number of articles to be packaged, whereas the present machine utilizes a strictly mechanical system by means of the turnover wheel, which is mechanically linked or geared to the remainder of the mechanism.
U.S. Pat. No. 5,235,796 issued on Aug. 17, 1993 to William A. Campbell, III et al., titled "Method And Apparatus For Packaging Articles," describes an electromechanical system for loading cookies from a conveyor into trays. The mechanism loads serially positioned articles from a conveyor into a generally vertically disposed holder, which pivots to drop the stack or slug into a tray positioned below the loader. The loader arm may include two separate compartments, for simultaneously loading two trays in tandem. No upwardly sloped stacking area, merging of plural lines into a single line, or purely mechanical means of determining the proper number of articles in a stack for transport to the wrapper is disclosed, as provided by the present mechanism.
U.S. Pat. No. 5,311,722 issued on May 17, 1994 to Colleen Staton, titled "Handling and Loading Batches Of Products On Edge," describes a conveyor system using a turnover wheel for stacking articles on edge from a tandem array on a first belt system. A plurality of permanently extended fingers or pins extend from the second belt system, to define the length of each assembled stack of articles. The first and second belt systems comprise a plurality of separate belts having a gap between each belt, in order to provide clearance for the extended pins. In contrast, the present system utilizes chain drives, with the trailing pins remaining permanently extended but with the leading pins being retractable and extendible in accordance with cam ramps located at predetermined positions along the chain run. The Staton system does not stack articles using a slope to define the stack, as in the present system, nor does Staton provide any means for merging two or more lines into a single line, as provided by the present infeed slug loader invention.
Swiss Patent Publication No. 376,047 published on Apr. 30, 1964 illustrates a conveyor packaging system utilizing a series of spacers along a belt or chain drive. The spacers are actuated to position themselves between horizontal slugs of articles on a lower belt or line, with the articles then being wrapped at the end of the line. No stacking mechanism is disclosed in the Swiss Patent Publication, as the articles are already stacked in the drawings. Moreover, the separating mechanism runs in an overhead conveyor, whereas the present machine utilizes underlying mechanisms.
Finally, British Patent Publication No. 1,444,277 published on Jul. 28, 1976 to Baker Perkins Holdings Limited, titled "Improvements In Wrapping Machines," describes a machine for handling a single line of previously formed horizontally disposed stacks or slugs of biscuits (the British term for cookies). A series of permanently extended fingers extends from an overhead conveyor to hold the leading and trailing units of each slug in place. When the slug reaches the wrapper, the overhead conveyor ends and two opposite side conveyors engage the wrapping material with flexible supports between each slug, in order to retain the integrity of each slug through the wrapping process. The British Patent Publication does not disclose any means for forming such slugs, as is accomplished by the present conveyor invention, but rather is directed to wrapping the previously formed slugs. Moreover, the British Patent Publication does not disclose any means of merging two or more slug lines into a single line, and utilizes an overhead conveyor with its potential drawbacks as discussed further above, unlike the present infeed slug loader invention.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.